He said Jackson's slide began with his addiction to painkillers after suffering burns in a Pepsi commercial in 1984. Then came the charges of child molestation first in 1993 and then in 2004. The final straw was the gruelling 50-concert tour at the age of 50.

Jackson paid $25 million in 1994 to the family of the first boy who accused him of molestation. The case of the second boy, which went to court, ended in his acquittal in 2005.

Quoting a letter from Jackson in the first molestation case, Halperin said: 'Michael was livid, he broke down in tears, he did not want to settle (by paying $25 million), he wanted to prove his innocence.'

In the second case, the boy, Gavin Arvizo, who accused Jackson of sexual touching, was drugged when he made his statement against the pop icon, the author said.

The family of the boy had 'a history of being fraudsters; they had tried this drill before on other people'. The case went to court and ended in Michael's acquittal in 2005.

'The child-molestation charges just drained him, in legal fees and also mentally,' the Canadian said.

'He has been the victim of extortionists, people who have come after him maliciously, and it's very sad.'

He said Michael had agreed to do the 10 concerts in London. 'But not the 50 (concerts) that were forced on him by his handlers who were drooling at the prospect of all that money.

'They (the handlers) never cared about him and just wanted to see what he could do for their own bank accounts.'

To infiltrate the Jackson camp, Halperin said, he befriended many people in Jackson's inner circle and went undercover as a hairdresser, taking a two-month course learning how to style hair.